Digestive System Quiz

a

A 25-year-old woman enters the hospital with persistent diarrhea and abdominal pain. An upper gastointestinal radiologic series suggests the presence of a duodenal ulcer, which is confirmed by enodscopy. The patients basal rate of secretion of gastric HCl is about 12 mmole/hr (the normal range is 1 to 5 mmole/hr). The patients gastrin level is 1145 pg/ml (the normal range is 50 to 150 pg/ml). When the patient's gastric juice is removed via a tube during a 24 hour period, the diarrhea is corrected. The patient also has moderate steatorrhea (excess fat in the stool). After a test meal, the patient's gastrin level is immediately tested and does not increase any more than the already high 1145 pg/ml. In the average normal individual, the same meal produces a doubling of gastrin levels. Infusion of exogenous secretin results in a peak serum gastrin level that is three times the basal level! In normal individuals, infusion of secretin results in a reduction of gastrin. The patient's rate of HCL secretion can be brought to lower levels by treatment with a histamine receptor blocker called cimetidine. However, the dose of cimetidine required to do this is several times greater than that usually used for patients with duodenal ulcers. Administration of an acetycholine blocker enhances the effect of cimetidine but still requires large doses. A single daily dose of a H+, K+ ATPase blocker called omeprazole is effective in bringing HCL secretion to below normal levels. Why does the patient have a duodenal ulcer? a. The amount of HCL leaving the stomach may be too great to be neutralized by pancreatic secretions b. The patient is likely suffering from a bacterial infection c. The increased gastrin stimulates a large drop in HCO3- secretion d. The inhibition of H+. K+ ATPase is the likely cause of the ulcer

d

A high level of sympathetic stimulation is MOST likely to cause which of the following effects on gastrointestinal function? a. Increase in gastric acid secretion b. Increase in mucous secretion c. Decrease in stomach pH (more acidic) d. Decrease in motility

b

A proteolytic enzyme secreted by the pancreas is a. ribonuclease. b. chymotrypsin. c. amylase. d. enterogastrone. e. pancreatic lipase.

b

Acid chyme is buffered by secreted from the pancreas. a. mucus b. bicarbonate c. ammonia d. urea

e

Amino acids and monosaccharides are absorbed in the , and fatty acids are absorbed in the . a. small intestine; large intestine b. small intestine; liver c. stomach; small intestine d. stomach; large intestine e. small intestine; small intestine too

c

Antihistamines would MOST limit the gastric secretion of a. pepsinogen. b. gastrin. c. hydrochloric acid. d. mucus.

e

Arrange the following events in the correct order: (1) absorption of lipids (2) emulsification (3) micelle formation (4) digestion of lipids a. 1, 2, 3, 4 b. 3, 4, 2, 1 c. 4, 1, 2, 3 d. 2, 4, 1, 3 e. 2, 4, 3, 1

e

Arrange the following in proper sequence: (1) digestion (2) elimination (3) ingestion (4) absorption a. 3, 4, 2, 1 b. 1, 4, 3, 2 c. 4, 1, 2, 3 d. 3, 4, 1, 2 e. 3, 1, 4, 2

a

Assume we could alter the conditions in the duodenum. If we inserted a large volume of highly acidic chyme which contained a large amount of fat, which of the following responses are consistent with that? (1) decreased gastric acid secretion (2) increased bile production (3) increased pancreatic bicarbonate production and pancreatic enzyme secretion (4) increased secretin and cholecystokinin a. 1, 2, 3, 4 b. 1, 2, 3 c. 2, 3, 4 d. 1, 3, 4 e. 1, 2, 4

a

Bacteria in the colon carry out all of the following EXCEPT... a. digest most of the proteins we get in the diet. b. synthesize vitamin K. c. produce some of the gases found in flatus. d. digest cellulose. e. form part of the feces.

b

Bile a. digests proteins in the small intestine. b. emulsifies fats in the small intestine. c. is made by the gallbladder and stored by the liver. d. activates trypsin in the small intestine. e. activates the pancreas.

c

Cholesterol produced by the body is transported in the blood as a. high-density. b. low-density. c. very low-density. d. medium-density.

a

Cholesterol removal from body cells is facilitated by lipoproteins. a. high-density b. low-density c. very low-density d. medium-density

a

Chylomicrons a. are synthesized in intestinal epithelial cells. b. enter capillaries in the small intestine. c. help emulsify fats. d. are a rich source of carbohydrate. e. are synthesized in the lumen of the small intestines.

b

Damage to the liver would MOST hamper digestion of a. carbohydrates. b. lipids. c. proteins. d. disaccharides.

c

Damage to which of the following nerves would reduce GI secretions? a. glossopharyngeal nerve b. hypoglossal nerve c. vagus nerve d. phrenic nerve

d

Emulsification a. converts small lipid droplets into larger droplets. b. occurs in the gallbladder. c. chemically digests lipids. d. increases surface area for lipid digestion. e. involves enzymes.

d

Enzymes for the digestion of disaccharides are produced in the a. mouth. b. stomach. c. pancreas. d. small intestine. e. liver.

a

Enzymes of the small intestine include a. disaccharidases. b. secretin. c. cholecystokinin. d. bile. e. histamine.

b

Fatty acids and certain lipids in the duodenum initiate the release of a. gastrin. b. cholecystokinin (CCK). c. gastrin and gastric inhibitory peptide. d. histamine e. somatomedin f. pepsinogen

d

Functions of the digestive system include all of the following except a. lipid emulsification. b. secretion of hormones into the blood stream. c. absorption. d. secretion of hormones into the duodenal lumen.

e

Functions of the liver include a. production of many blood proteins. b. interconversion of nutrients. c. detoxification of harmful chemicals. d. bile production. e. All of these choices are correct.

a

How does omeprazole decrease the patients rate of HCL secretion and why is only one dose per day required? a. Omeprazole blocks the H+/K+ ATPase transporter and does so with a covalent bond so that it completely shuts off the transporter until new transporters are synthesized by the cell b. Ompeprazole is an acetycholine agonist and is therefore able to stimulate more efficient regulation of stomach secretions. c. Omeprazole is a powerful somatostatin antagonist and is able to stop the actions of the D cells. d. Omeprazole is a powerful histamine inhibitor and is able to stop the stimulation of parietal cells.

c

Hydrochloric acid (HCL) is secreted by cells. a. mucous b. regenerative or stem c. parietal d. chief e. enteroendocrine or ECL

c

If the thoracic duct were tied off, which of the following classes of nutrients would not enter the circulatory system at their normal rate? a. amino acids b. glucose c. lipids d. disaccharides e. monosaccharides

b

If you ate a piece of pizza, where would the majority of the chemical digestion for the crust occur? a. Stomach b. Small Intestine c. Large Intestine d. Liver

d

Imagine a drug that could block carbonic anhydrase. Which of the following would be TRUE? a. Less CO2 would be exhaled at the lung b. Less stomach acid would be created c. Less HCO3- would be secreted by the exocrinie pancreas d. All of the above are actually TRUE

d

In which of the following areas does carbohydrate digestion occur? a. mouth and stomach b. duodenum and pancreas c. stomach and pancreas d. mouth and duodenum

c

Inhibition of exocrine pancreatic secretions would likely result in a. decreased insulin secretion following meals b. decreased bile synthesis and secretion c. an acidic chyme d. increased protein absorbtion in the illeum

c

LDL's are taken into a cell by the process of a. simple diffusion. b. osmosis. c. receptor mediated endocytosis. d. HDL carrier molecules. e. facilitated diffusion.

c

Lipid digestion and absorption requires the coordinated actions of and . a. hydrochloric acid and pepsin b. bile and amylase c. lipase and bile d. water and bile

f

Match the secretion with the correct cell type. a. hydrochloric acid = parietal cells b. bile = hepatocyte c. gastrin = endocrine cells d. trypsin = acinar cells e. mucus = goblet cells f. All of the above matches are correct g. None of the above matches are correct

b

Most glucose is absorbed in the epithelial cells of the small intestine by a. simple diffusion b. secondary active transport with Na+ c. passive diffusion d. phagocytosis

b

Most nutrient absorption occurs in the a. stomach and esophagus. b. duodenum and the rest of the small intestine. c. ascending colon and cecum. d. pancreatic duct and gall bladder. e. ileum and transverse colon.

c

Most protein digestion occurs in the a. mouth and esophagus. b. stomach and duodenum. c. duodenum and jejunum. d. pancreas and duodenum.

b

Nutrient-rich blood from the digestive tract comes to the liver by way of the a. hepatic artery. b. hepatic portal vein. c. hepatic vein. d. inferior vena cava. e. celiac trunk.

a

One of the primary functions of the large intestine is a. water reabsorption. b. mineral absorption. c. hormone degradation. d. degrading toxins.

b

Pancreatic enzymes are secreted in response to the hormone a. insulin. b. cholecystokinin (CCK). c. secretin. d. glucagon. e. gastrin.

a

Pepsin is produced by ________ cells and is activated by . a. chief; HCl secreted by parietal cells b. chief; carbonic anhydrase secreted by parietal cells c. parietal; HCl secreted by chief cells d. parietal; carbonic anhydrase secreted by chief cells e. exocrine cells; carbonic anhydrase secreted by parietal cells

d

Pepsin would have the greatest activity a. immediately upon secretion into the stomach. b. immediately upon entering the duodenum. c. when the pH of the chyme is greater than 3. d. when the pH of the chyme is less than 3.

b

Pepsin would not be found in the stomach if the cells were destroyed. 1. goblet 2. parietal 3. D cells 4. chief or zymogenic a. 1,2 b. 2,4 c. 3 d. 4 e. 2

d

Pepsin would not be fround in the stomach if the were destroyed. a. goblet cells b. parietal cells c. D cells d. chief cells

c

Pernicious anemia develops if there is a vitamin deficiency. a. C b. B6 c. B12 d. D

b

Phil R. Awp works as a gas station attendant. Lately, he has been experiencing terrible heart burn (because of too much stomach acid). He recently received a prescription for a drug that is supposed to help. Which of the following drugs is MOST LIKELY going to help Phil? a. A drug that increases the muscle tone of the pyloric sphincter b. A drug that inhibits Enterochromaffin-like (ECL) cells c. A drug that stimulates the parasympathetic nervous system d. A drug that stimulates the release of Gastrin e. A drug that inhibits the release of Somatostatin f. Actually any or all of the above should help

b

SGLT, a transport pump of the small intestine, can only absorb glucose by simultaneously transporting a. water. b. sodium. c. maltose. d. amino acids. e. potassium.

b

Secretion of insulin from the pancreas is increased in response to a. increased cholecystokinin. b. increased gastric inhibitory peptide. c. increased histamine. d. increased glucagon.

b

Small droplets of digested lipids surrounded by bile salts are called a. chylomicrons. b. micelles. c. monoglycerides. d. diglycerides. e. lacteals.

d

Somatostatin is produced in the stomach by a. goblet cells. b. parietal cells. c. G cells. d. D cells.

a

The acidic chyme entering the duodenum initiates all of the following actions EXCEPT: a. the release of intrinsic factor b. the release of secretin from the duodenum c. the release of bicarbonate from the pancreas d. the release of bicarbonate into bile

c

The enzymes for digestion of carbohydrates come from all of the following EXCEPT the a. pancreas. b. duodenum. c. liver. d. salivary glands.

a

The formation of HCl in the stomach involves the a. active transport of hydrogen ions from parietal cells into the lumen of the stomach in exchange for K+ b. exchange of sodium ions for hydrogen ions in the transport process. c. exchange of sodium and bicarbonate ions. d. all of the above

c

The gallbladder a. produces bile. b. is attached to the pancreas. c. stores bile. d. produces secretin. e. breaks down red blood cells.

b

The gallbladder contracts in response to the hormone a. secretin. b. cholecystokinin. c. gastrin. d. enterokinin. e. insulin.

a

The liver a. produces secretions that help neutralize stomach acids and emulsify fats. b. produces several digestive enzymes. c. stores vitamin C. d. receives oxygenated blood from the portal vein. e. All of the above

c

The of the stomach and intestine secrete histamine a. G cells b. parietal cells c. enterochromaffin-like (ECL) cells d. chief cells

c

The of the stomach and intestine secrete histamine. a. G cells b. parietal cells c. enterochromaffin-like (ECL) cells d. chief cells

e

The pancreatic islets a. are found in the wall of the stomach. b. excrete mucus. c. produce digestive enzymes. d. are exocrine glands. e. are endocrine glands.

b

The stomach churns food into a pasty material called a. a bolus b. chyme c. chyle d. saliva e. cholecystokinin

b

Trypsin can activate a. pepsinogen. b. chymotrypsinogen. c. angiotensinogen. d. endopeptidase. e. lipase.

a

Trypsin is activated by the enzyme a. enterokinase. b. lipase. c. lactase. d. carboxypeptidase.

a

Vesicles include a phospholipid membrane, but very little protein. These vesicles would contain cholesterol and triglycerides. These vesicles would probably be at a higher concentration in the superior vena cava than the hepatic portal vein. These vesicles are synthesized by columnar cells in the small intestine. This sounds like ... a. Chylomicrons b. LDLs c. HDLs d. Bile e. Glycogen

c

Vitamin B12 is primarily absorbed in the a. duodenum. b. stomach. c. ileum. d. colon.

b

When chyme enters the duodenum, is released and stimulates the pancreas to secrete bicarbonates. a. gastrin b. secretin c. insulin d. cholecystokinin e. glucagon

b

Which is not a function of cholecystokinin? a. Inhibits gastric secretions. b. Inhibits pancreatic secretions c. Decreases gastric motility d. Increases contraction of the gallblader

a

Which layer of the digestive tract is in direct contact with the food consumed? a. mucosa b. muscularis c. submucosa d. serosa e. peritoneum

e

Which of the following GI tract layers is correctly matched? a. mucosa - controls peristalsis b. serosa - contains an extensive supply of nerves and blood vessels c. submucosa - lamina propria d. serosa - increased surface area e. muscularis - responsible for peristalsis

a

Which of the following characterizes carbohydrate digestion? a. It begins when food comes in contact with saliva b. It begins when food comes in contact with gastric juice c. It begins when food comes in contact with pancreatic secretions d. It begins when food comes into contact with sucrase

c

Which of the following does not illustrate digestion? a. polysaccharides → disaccharides b. fat → fatty acids and glycerol c. CO2 and H2O → carbohydrates d. protein → amino acids e. disaccharides → monosaccharides

c

Which of the following enzymes functions at the lowest pH? a. salivary amylase b. pancreatic amylase c. pepsin d. trypsin e. dipeptidase

c

Which of the following events occurs because of the low pH of the stomach? a. activation of salivary amylase b. enhanced carbohydrate digestion c. proper environment for functioning of pepsin d. protein synthesis e. lipid digestion

e

Which of the following is not part of the gastrointestinal tract? a. pharynx b. liver c. small intestine d. esophagus e. kidney

b

Which of the following is the MOST likely abnormality that could lead to elevated gastrin levels in this patient? a. This patient could be have a lack of parasympathetic control of the digestive systems. b. This patient could have a tumor in the pancreas that pathologically secretes gastrin c. This patient could have overexpression of endocrine D cells which release somatotstatin d. This patient could be experiencing a lot of stress and have excessive sympathetic activity working on their GI system

a

Which of the following lipoproteins contains the highest percentage of cholesterol? a. LDL b. HDL c. VLDL d. chylomicron e. CDL

a

Which of the following statements concerning cholecystokinin is correct? a. Cholecystokinin stimulates contraction of the gallbladder. b. Cholecystokinin stimulates secretion of mucus by the gastric glands. c. Cholecystokinin stimulates the pancreas to release a bicarbonate-rich solution. d. Cholecystokinin stimulates the intestine to secrete trypsin. e. Cholecystokinin stimulates gastric secretions. f. All of the above

c

Which of the following statements regarding the pancreas is true? a. The head of the pancreas lies in the curvature of the ileum. b. The pancreatic duct carries both enzymes and hormones. c. The pancreatic acinar cells secrete digestive enzymes. d. The pancreas assists the stomach in the production of acid.

b

Which of the following would be MOST beneficial in treating gastric ulcers? a. epinephrine b. histamine blockers c. gastric inhibitory peptide d. carboxypeptidase

c

Which of the following would be MOST important for digestion of fat? a. Parotid Gland and saliva b. Stomach and acid c. Gallbladder and bile d. Large intestine and water

c

Which of the following would inhibit both gastric secretion and gastric motility? a. vagal stimulation and gastrin b. chewing and swallowing food c. gastric inhibitory peptide (GIP) d. gastrin and cholecystokinin (CCK) e. large amounts of fiber in the diet

c

Which of the following would stimulate gastric acid secretion? a. acidic chyme in duodenum b. secretin c. gastrin d. cholecystokinin e. pepsin

e

Which of these is not a component of the pancreatic juice? a. trypsinogen b. chymotrypsinogen c. deoxyribonuclease d. sodium bicarbonate e. enterokinase

a

Which of these nutrients is absorbed by the lacteals (lymphatic system) of the small intestine? a. triglycerides b. amino acids c. glucose d. minerals e. water, soluble vitamins

d

Why are several digestive enzymes secreted as zymogens? a. because this saves one step in their synthesis b. because gastric cells do not have the necessary enzymes for their synthesis c. so they start digesting intracellular proteins of the gastric cells more quickly d. so they act only in the lumen and do not digest the tissues that secrete them e. so they can start digesting dietary proteins more quickly

b

With regard to protein absorption in the small intestine, which statement/s is/are correct: 1. Some intact protein can be absorbed 2. Sodium is directly involved in the absorption of amino acids 3. Pepsin is the most important protease for protein digestion 4. Single amino acids enter intestinal cells through the GLUT 5 receptor 5. Pancreatic amylase is essential for protein digestion 6. The stomach is the MOST important organ for carbohydrate digestion a. 1,2,3,5 b. 1,2 c. 2,3 d. 2,3,4,5,6 e. 3,5,6 f. 1,4 g. 1,3

c

is required for the intestinal absorption of vitamin B12. a. Vitamin D b. Calcium c. Intrinsic Factor d. Vitamin C e. Secretin

d

is the physiological process that moves a nutrient from the lumen to the circulating blood. a. Ingestion b. Compaction c. Digestion d. Absorption e. Secretion

c

stimulates ECL cells to secrete histamine which stimulates HCl release from parietal cells. a. Secretin b. CCK c. Gastrin d. GIP